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-rw-r--r--src/basic/btrfs-util.c2075
1 files changed, 0 insertions, 2075 deletions
diff --git a/src/basic/btrfs-util.c b/src/basic/btrfs-util.c
deleted file mode 100644
index 359d85f2e8..0000000000
--- a/src/basic/btrfs-util.c
+++ /dev/null
@@ -1,2075 +0,0 @@
-/***
- This file is part of systemd.
-
- Copyright 2014 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <errno.h>
-#include <fcntl.h>
-#include <inttypes.h>
-#include <linux/loop.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/statfs.h>
-#include <sys/sysmacros.h>
-#include <unistd.h>
-
-#ifdef HAVE_LINUX_BTRFS_H
-#include <linux/btrfs.h>
-#endif
-
-#include "alloc-util.h"
-#include "btrfs-ctree.h"
-#include "btrfs-util.h"
-#include "copy.h"
-#include "fd-util.h"
-#include "fileio.h"
-#include "io-util.h"
-#include "macro.h"
-#include "missing.h"
-#include "path-util.h"
-#include "selinux-util.h"
-#include "smack-util.h"
-#include "sparse-endian.h"
-#include "stat-util.h"
-#include "string-util.h"
-#include "time-util.h"
-#include "util.h"
-
-/* WARNING: Be careful with file system ioctls! When we get an fd, we
- * need to make sure it either refers to only a regular file or
- * directory, or that it is located on btrfs, before invoking any
- * btrfs ioctls. The ioctl numbers are reused by some device drivers
- * (such as DRM), and hence might have bad effects when invoked on
- * device nodes (that reference drivers) rather than fds to normal
- * files or directories. */
-
-static int validate_subvolume_name(const char *name) {
-
- if (!filename_is_valid(name))
- return -EINVAL;
-
- if (strlen(name) > BTRFS_SUBVOL_NAME_MAX)
- return -E2BIG;
-
- return 0;
-}
-
-static int open_parent(const char *path, int flags) {
- _cleanup_free_ char *parent = NULL;
- int fd;
-
- assert(path);
-
- parent = dirname_malloc(path);
- if (!parent)
- return -ENOMEM;
-
- fd = open(parent, flags);
- if (fd < 0)
- return -errno;
-
- return fd;
-}
-
-static int extract_subvolume_name(const char *path, const char **subvolume) {
- const char *fn;
- int r;
-
- assert(path);
- assert(subvolume);
-
- fn = basename(path);
-
- r = validate_subvolume_name(fn);
- if (r < 0)
- return r;
-
- *subvolume = fn;
- return 0;
-}
-
-int btrfs_is_filesystem(int fd) {
- struct statfs sfs;
-
- assert(fd >= 0);
-
- if (fstatfs(fd, &sfs) < 0)
- return -errno;
-
- return F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC);
-}
-
-int btrfs_is_subvol_fd(int fd) {
- struct stat st;
-
- assert(fd >= 0);
-
- /* On btrfs subvolumes always have the inode 256 */
-
- if (fstat(fd, &st) < 0)
- return -errno;
-
- if (!S_ISDIR(st.st_mode) || st.st_ino != 256)
- return 0;
-
- return btrfs_is_filesystem(fd);
-}
-
-int btrfs_is_subvol(const char *path) {
- _cleanup_close_ int fd = -1;
-
- assert(path);
-
- fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (fd < 0)
- return -errno;
-
- return btrfs_is_subvol_fd(fd);
-}
-
-int btrfs_subvol_make(const char *path) {
- struct btrfs_ioctl_vol_args args = {};
- _cleanup_close_ int fd = -1;
- const char *subvolume;
- int r;
-
- assert(path);
-
- r = extract_subvolume_name(path, &subvolume);
- if (r < 0)
- return r;
-
- fd = open_parent(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (fd < 0)
- return fd;
-
- strncpy(args.name, subvolume, sizeof(args.name)-1);
-
- if (ioctl(fd, BTRFS_IOC_SUBVOL_CREATE, &args) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_subvol_make_label(const char *path) {
- int r;
-
- assert(path);
-
- r = mac_selinux_create_file_prepare(path, S_IFDIR);
- if (r < 0)
- return r;
-
- r = btrfs_subvol_make(path);
- mac_selinux_create_file_clear();
-
- if (r < 0)
- return r;
-
- return mac_smack_fix(path, false, false);
-}
-
-int btrfs_subvol_set_read_only_fd(int fd, bool b) {
- uint64_t flags, nflags;
- struct stat st;
-
- assert(fd >= 0);
-
- if (fstat(fd, &st) < 0)
- return -errno;
-
- if (!S_ISDIR(st.st_mode) || st.st_ino != 256)
- return -EINVAL;
-
- if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) < 0)
- return -errno;
-
- if (b)
- nflags = flags | BTRFS_SUBVOL_RDONLY;
- else
- nflags = flags & ~BTRFS_SUBVOL_RDONLY;
-
- if (flags == nflags)
- return 0;
-
- if (ioctl(fd, BTRFS_IOC_SUBVOL_SETFLAGS, &nflags) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_subvol_set_read_only(const char *path, bool b) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (fd < 0)
- return -errno;
-
- return btrfs_subvol_set_read_only_fd(fd, b);
-}
-
-int btrfs_subvol_get_read_only_fd(int fd) {
- uint64_t flags;
- struct stat st;
-
- assert(fd >= 0);
-
- if (fstat(fd, &st) < 0)
- return -errno;
-
- if (!S_ISDIR(st.st_mode) || st.st_ino != 256)
- return -EINVAL;
-
- if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) < 0)
- return -errno;
-
- return !!(flags & BTRFS_SUBVOL_RDONLY);
-}
-
-int btrfs_reflink(int infd, int outfd) {
- struct stat st;
- int r;
-
- assert(infd >= 0);
- assert(outfd >= 0);
-
- /* Make sure we invoke the ioctl on a regular file, so that no
- * device driver accidentally gets it. */
-
- if (fstat(outfd, &st) < 0)
- return -errno;
-
- if (!S_ISREG(st.st_mode))
- return -EINVAL;
-
- r = ioctl(outfd, BTRFS_IOC_CLONE, infd);
- if (r < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_clone_range(int infd, uint64_t in_offset, int outfd, uint64_t out_offset, uint64_t sz) {
- struct btrfs_ioctl_clone_range_args args = {
- .src_fd = infd,
- .src_offset = in_offset,
- .src_length = sz,
- .dest_offset = out_offset,
- };
- struct stat st;
- int r;
-
- assert(infd >= 0);
- assert(outfd >= 0);
- assert(sz > 0);
-
- if (fstat(outfd, &st) < 0)
- return -errno;
-
- if (!S_ISREG(st.st_mode))
- return -EINVAL;
-
- r = ioctl(outfd, BTRFS_IOC_CLONE_RANGE, &args);
- if (r < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_get_block_device_fd(int fd, dev_t *dev) {
- struct btrfs_ioctl_fs_info_args fsi = {};
- uint64_t id;
- int r;
-
- assert(fd >= 0);
- assert(dev);
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
-
- if (ioctl(fd, BTRFS_IOC_FS_INFO, &fsi) < 0)
- return -errno;
-
- /* We won't do this for btrfs RAID */
- if (fsi.num_devices != 1)
- return 0;
-
- for (id = 1; id <= fsi.max_id; id++) {
- struct btrfs_ioctl_dev_info_args di = {
- .devid = id,
- };
- struct stat st;
-
- if (ioctl(fd, BTRFS_IOC_DEV_INFO, &di) < 0) {
- if (errno == ENODEV)
- continue;
-
- return -errno;
- }
-
- if (stat((char*) di.path, &st) < 0)
- return -errno;
-
- if (!S_ISBLK(st.st_mode))
- return -ENODEV;
-
- if (major(st.st_rdev) == 0)
- return -ENODEV;
-
- *dev = st.st_rdev;
- return 1;
- }
-
- return -ENODEV;
-}
-
-int btrfs_get_block_device(const char *path, dev_t *dev) {
- _cleanup_close_ int fd = -1;
-
- assert(path);
- assert(dev);
-
- fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC);
- if (fd < 0)
- return -errno;
-
- return btrfs_get_block_device_fd(fd, dev);
-}
-
-int btrfs_subvol_get_id_fd(int fd, uint64_t *ret) {
- struct btrfs_ioctl_ino_lookup_args args = {
- .objectid = BTRFS_FIRST_FREE_OBJECTID
- };
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
-
- if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args) < 0)
- return -errno;
-
- *ret = args.treeid;
- return 0;
-}
-
-int btrfs_subvol_get_id(int fd, const char *subvol, uint64_t *ret) {
- _cleanup_close_ int subvol_fd = -1;
-
- assert(fd >= 0);
- assert(ret);
-
- subvol_fd = openat(fd, subvol, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (subvol_fd < 0)
- return -errno;
-
- return btrfs_subvol_get_id_fd(subvol_fd, ret);
-}
-
-static bool btrfs_ioctl_search_args_inc(struct btrfs_ioctl_search_args *args) {
- assert(args);
-
- /* the objectid, type, offset together make up the btrfs key,
- * which is considered a single 136byte integer when
- * comparing. This call increases the counter by one, dealing
- * with the overflow between the overflows */
-
- if (args->key.min_offset < (uint64_t) -1) {
- args->key.min_offset++;
- return true;
- }
-
- if (args->key.min_type < (uint8_t) -1) {
- args->key.min_type++;
- args->key.min_offset = 0;
- return true;
- }
-
- if (args->key.min_objectid < (uint64_t) -1) {
- args->key.min_objectid++;
- args->key.min_offset = 0;
- args->key.min_type = 0;
- return true;
- }
-
- return 0;
-}
-
-static void btrfs_ioctl_search_args_set(struct btrfs_ioctl_search_args *args, const struct btrfs_ioctl_search_header *h) {
- assert(args);
- assert(h);
-
- args->key.min_objectid = h->objectid;
- args->key.min_type = h->type;
- args->key.min_offset = h->offset;
-}
-
-static int btrfs_ioctl_search_args_compare(const struct btrfs_ioctl_search_args *args) {
- assert(args);
-
- /* Compare min and max */
-
- if (args->key.min_objectid < args->key.max_objectid)
- return -1;
- if (args->key.min_objectid > args->key.max_objectid)
- return 1;
-
- if (args->key.min_type < args->key.max_type)
- return -1;
- if (args->key.min_type > args->key.max_type)
- return 1;
-
- if (args->key.min_offset < args->key.max_offset)
- return -1;
- if (args->key.min_offset > args->key.max_offset)
- return 1;
-
- return 0;
-}
-
-#define FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) \
- for ((i) = 0, \
- (sh) = (const struct btrfs_ioctl_search_header*) (args).buf; \
- (i) < (args).key.nr_items; \
- (i)++, \
- (sh) = (const struct btrfs_ioctl_search_header*) ((uint8_t*) (sh) + sizeof(struct btrfs_ioctl_search_header) + (sh)->len))
-
-#define BTRFS_IOCTL_SEARCH_HEADER_BODY(sh) \
- ((void*) ((uint8_t*) sh + sizeof(struct btrfs_ioctl_search_header)))
-
-int btrfs_subvol_get_info_fd(int fd, uint64_t subvol_id, BtrfsSubvolInfo *ret) {
- struct btrfs_ioctl_search_args args = {
- /* Tree of tree roots */
- .key.tree_id = BTRFS_ROOT_TREE_OBJECTID,
-
- /* Look precisely for the subvolume items */
- .key.min_type = BTRFS_ROOT_ITEM_KEY,
- .key.max_type = BTRFS_ROOT_ITEM_KEY,
-
- .key.min_offset = 0,
- .key.max_offset = (uint64_t) -1,
-
- /* No restrictions on the other components */
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- bool found = false;
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- if (subvol_id == 0) {
- r = btrfs_subvol_get_id_fd(fd, &subvol_id);
- if (r < 0)
- return r;
- } else {
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
- }
-
- args.key.min_objectid = args.key.max_objectid = subvol_id;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0)
- return -errno;
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
-
- const struct btrfs_root_item *ri;
-
- /* Make sure we start the next search at least from this entry */
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->objectid != subvol_id)
- continue;
- if (sh->type != BTRFS_ROOT_ITEM_KEY)
- continue;
-
- /* Older versions of the struct lacked the otime setting */
- if (sh->len < offsetof(struct btrfs_root_item, otime) + sizeof(struct btrfs_timespec))
- continue;
-
- ri = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
-
- ret->otime = (usec_t) le64toh(ri->otime.sec) * USEC_PER_SEC +
- (usec_t) le32toh(ri->otime.nsec) / NSEC_PER_USEC;
-
- ret->subvol_id = subvol_id;
- ret->read_only = !!(le64toh(ri->flags) & BTRFS_ROOT_SUBVOL_RDONLY);
-
- assert_cc(sizeof(ri->uuid) == sizeof(ret->uuid));
- memcpy(&ret->uuid, ri->uuid, sizeof(ret->uuid));
- memcpy(&ret->parent_uuid, ri->parent_uuid, sizeof(ret->parent_uuid));
-
- found = true;
- goto finish;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
-finish:
- if (!found)
- return -ENODATA;
-
- return 0;
-}
-
-int btrfs_qgroup_get_quota_fd(int fd, uint64_t qgroupid, BtrfsQuotaInfo *ret) {
-
- struct btrfs_ioctl_search_args args = {
- /* Tree of quota items */
- .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID,
-
- /* The object ID is always 0 */
- .key.min_objectid = 0,
- .key.max_objectid = 0,
-
- /* Look precisely for the quota items */
- .key.min_type = BTRFS_QGROUP_STATUS_KEY,
- .key.max_type = BTRFS_QGROUP_LIMIT_KEY,
-
- /* No restrictions on the other components */
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- bool found_info = false, found_limit = false;
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- if (qgroupid == 0) {
- r = btrfs_subvol_get_id_fd(fd, &qgroupid);
- if (r < 0)
- return r;
- } else {
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
- }
-
- args.key.min_offset = args.key.max_offset = qgroupid;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) {
- if (errno == ENOENT) /* quota tree is missing: quota disabled */
- break;
-
- return -errno;
- }
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
-
- /* Make sure we start the next search at least from this entry */
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->objectid != 0)
- continue;
- if (sh->offset != qgroupid)
- continue;
-
- if (sh->type == BTRFS_QGROUP_INFO_KEY) {
- const struct btrfs_qgroup_info_item *qii = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
-
- ret->referenced = le64toh(qii->rfer);
- ret->exclusive = le64toh(qii->excl);
-
- found_info = true;
-
- } else if (sh->type == BTRFS_QGROUP_LIMIT_KEY) {
- const struct btrfs_qgroup_limit_item *qli = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
-
- if (le64toh(qli->flags) & BTRFS_QGROUP_LIMIT_MAX_RFER)
- ret->referenced_max = le64toh(qli->max_rfer);
- else
- ret->referenced_max = (uint64_t) -1;
-
- if (le64toh(qli->flags) & BTRFS_QGROUP_LIMIT_MAX_EXCL)
- ret->exclusive_max = le64toh(qli->max_excl);
- else
- ret->exclusive_max = (uint64_t) -1;
-
- found_limit = true;
- }
-
- if (found_info && found_limit)
- goto finish;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
-finish:
- if (!found_limit && !found_info)
- return -ENODATA;
-
- if (!found_info) {
- ret->referenced = (uint64_t) -1;
- ret->exclusive = (uint64_t) -1;
- }
-
- if (!found_limit) {
- ret->referenced_max = (uint64_t) -1;
- ret->exclusive_max = (uint64_t) -1;
- }
-
- return 0;
-}
-
-int btrfs_qgroup_get_quota(const char *path, uint64_t qgroupid, BtrfsQuotaInfo *ret) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_qgroup_get_quota_fd(fd, qgroupid, ret);
-}
-
-int btrfs_subvol_find_subtree_qgroup(int fd, uint64_t subvol_id, uint64_t *ret) {
- uint64_t level, lowest = (uint64_t) -1, lowest_qgroupid = 0;
- _cleanup_free_ uint64_t *qgroups = NULL;
- int r, n, i;
-
- assert(fd >= 0);
- assert(ret);
-
- /* This finds the "subtree" qgroup for a specific
- * subvolume. This only works for subvolumes that have been
- * prepared with btrfs_subvol_auto_qgroup_fd() with
- * insert_intermediary_qgroup=true (or equivalent). For others
- * it will return the leaf qgroup instead. The two cases may
- * be distuingished via the return value, which is 1 in case
- * an appropriate "subtree" qgroup was found, and 0
- * otherwise. */
-
- if (subvol_id == 0) {
- r = btrfs_subvol_get_id_fd(fd, &subvol_id);
- if (r < 0)
- return r;
- }
-
- r = btrfs_qgroupid_split(subvol_id, &level, NULL);
- if (r < 0)
- return r;
- if (level != 0) /* Input must be a leaf qgroup */
- return -EINVAL;
-
- n = btrfs_qgroup_find_parents(fd, subvol_id, &qgroups);
- if (n < 0)
- return n;
-
- for (i = 0; i < n; i++) {
- uint64_t id;
-
- r = btrfs_qgroupid_split(qgroups[i], &level, &id);
- if (r < 0)
- return r;
-
- if (id != subvol_id)
- continue;
-
- if (lowest == (uint64_t) -1 || level < lowest) {
- lowest_qgroupid = qgroups[i];
- lowest = level;
- }
- }
-
- if (lowest == (uint64_t) -1) {
- /* No suitable higher-level qgroup found, let's return
- * the leaf qgroup instead, and indicate that with the
- * return value. */
-
- *ret = subvol_id;
- return 0;
- }
-
- *ret = lowest_qgroupid;
- return 1;
-}
-
-int btrfs_subvol_get_subtree_quota_fd(int fd, uint64_t subvol_id, BtrfsQuotaInfo *ret) {
- uint64_t qgroupid;
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- /* This determines the quota data of the qgroup with the
- * lowest level, that shares the id part with the specified
- * subvolume. This is useful for determining the quota data
- * for entire subvolume subtrees, as long as the subtrees have
- * been set up with btrfs_qgroup_subvol_auto_fd() or in a
- * compatible way */
-
- r = btrfs_subvol_find_subtree_qgroup(fd, subvol_id, &qgroupid);
- if (r < 0)
- return r;
-
- return btrfs_qgroup_get_quota_fd(fd, qgroupid, ret);
-}
-
-int btrfs_subvol_get_subtree_quota(const char *path, uint64_t subvol_id, BtrfsQuotaInfo *ret) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_subvol_get_subtree_quota_fd(fd, subvol_id, ret);
-}
-
-int btrfs_defrag_fd(int fd) {
- struct stat st;
-
- assert(fd >= 0);
-
- if (fstat(fd, &st) < 0)
- return -errno;
-
- if (!S_ISREG(st.st_mode))
- return -EINVAL;
-
- if (ioctl(fd, BTRFS_IOC_DEFRAG, NULL) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_defrag(const char *p) {
- _cleanup_close_ int fd = -1;
-
- fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_defrag_fd(fd);
-}
-
-int btrfs_quota_enable_fd(int fd, bool b) {
- struct btrfs_ioctl_quota_ctl_args args = {
- .cmd = b ? BTRFS_QUOTA_CTL_ENABLE : BTRFS_QUOTA_CTL_DISABLE,
- };
- int r;
-
- assert(fd >= 0);
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
-
- if (ioctl(fd, BTRFS_IOC_QUOTA_CTL, &args) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_quota_enable(const char *path, bool b) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_quota_enable_fd(fd, b);
-}
-
-int btrfs_qgroup_set_limit_fd(int fd, uint64_t qgroupid, uint64_t referenced_max) {
-
- struct btrfs_ioctl_qgroup_limit_args args = {
- .lim.max_rfer = referenced_max,
- .lim.flags = BTRFS_QGROUP_LIMIT_MAX_RFER,
- };
- unsigned c;
- int r;
-
- assert(fd >= 0);
-
- if (qgroupid == 0) {
- r = btrfs_subvol_get_id_fd(fd, &qgroupid);
- if (r < 0)
- return r;
- } else {
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
- }
-
- args.qgroupid = qgroupid;
-
- for (c = 0;; c++) {
- if (ioctl(fd, BTRFS_IOC_QGROUP_LIMIT, &args) < 0) {
-
- if (errno == EBUSY && c < 10) {
- (void) btrfs_quota_scan_wait(fd);
- continue;
- }
-
- return -errno;
- }
-
- break;
- }
-
- return 0;
-}
-
-int btrfs_qgroup_set_limit(const char *path, uint64_t qgroupid, uint64_t referenced_max) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_qgroup_set_limit_fd(fd, qgroupid, referenced_max);
-}
-
-int btrfs_subvol_set_subtree_quota_limit_fd(int fd, uint64_t subvol_id, uint64_t referenced_max) {
- uint64_t qgroupid;
- int r;
-
- assert(fd >= 0);
-
- r = btrfs_subvol_find_subtree_qgroup(fd, subvol_id, &qgroupid);
- if (r < 0)
- return r;
-
- return btrfs_qgroup_set_limit_fd(fd, qgroupid, referenced_max);
-}
-
-int btrfs_subvol_set_subtree_quota_limit(const char *path, uint64_t subvol_id, uint64_t referenced_max) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd < 0)
- return -errno;
-
- return btrfs_subvol_set_subtree_quota_limit_fd(fd, subvol_id, referenced_max);
-}
-
-int btrfs_resize_loopback_fd(int fd, uint64_t new_size, bool grow_only) {
- struct btrfs_ioctl_vol_args args = {};
- _cleanup_free_ char *p = NULL, *loop = NULL, *backing = NULL;
- _cleanup_close_ int loop_fd = -1, backing_fd = -1;
- struct stat st;
- dev_t dev = 0;
- int r;
-
- /* In contrast to btrfs quota ioctls ftruncate() cannot make sense of "infinity" or file sizes > 2^31 */
- if (!FILE_SIZE_VALID(new_size))
- return -EINVAL;
-
- /* btrfs cannot handle file systems < 16M, hence use this as minimum */
- if (new_size < 16*1024*1024)
- new_size = 16*1024*1024;
-
- r = btrfs_get_block_device_fd(fd, &dev);
- if (r < 0)
- return r;
- if (r == 0)
- return -ENODEV;
-
- if (asprintf(&p, "/sys/dev/block/%u:%u/loop/backing_file", major(dev), minor(dev)) < 0)
- return -ENOMEM;
- r = read_one_line_file(p, &backing);
- if (r == -ENOENT)
- return -ENODEV;
- if (r < 0)
- return r;
- if (isempty(backing) || !path_is_absolute(backing))
- return -ENODEV;
-
- backing_fd = open(backing, O_RDWR|O_CLOEXEC|O_NOCTTY);
- if (backing_fd < 0)
- return -errno;
-
- if (fstat(backing_fd, &st) < 0)
- return -errno;
- if (!S_ISREG(st.st_mode))
- return -ENODEV;
-
- if (new_size == (uint64_t) st.st_size)
- return 0;
-
- if (grow_only && new_size < (uint64_t) st.st_size)
- return -EINVAL;
-
- if (asprintf(&loop, "/dev/block/%u:%u", major(dev), minor(dev)) < 0)
- return -ENOMEM;
- loop_fd = open(loop, O_RDWR|O_CLOEXEC|O_NOCTTY);
- if (loop_fd < 0)
- return -errno;
-
- if (snprintf(args.name, sizeof(args.name), "%" PRIu64, new_size) >= (int) sizeof(args.name))
- return -EINVAL;
-
- if (new_size < (uint64_t) st.st_size) {
- /* Decrease size: first decrease btrfs size, then shorten loopback */
- if (ioctl(fd, BTRFS_IOC_RESIZE, &args) < 0)
- return -errno;
- }
-
- if (ftruncate(backing_fd, new_size) < 0)
- return -errno;
-
- if (ioctl(loop_fd, LOOP_SET_CAPACITY, 0) < 0)
- return -errno;
-
- if (new_size > (uint64_t) st.st_size) {
- /* Increase size: first enlarge loopback, then increase btrfs size */
- if (ioctl(fd, BTRFS_IOC_RESIZE, &args) < 0)
- return -errno;
- }
-
- /* Make sure the free disk space is correctly updated for both file systems */
- (void) fsync(fd);
- (void) fsync(backing_fd);
-
- return 1;
-}
-
-int btrfs_resize_loopback(const char *p, uint64_t new_size, bool grow_only) {
- _cleanup_close_ int fd = -1;
-
- fd = open(p, O_RDONLY|O_NOCTTY|O_CLOEXEC);
- if (fd < 0)
- return -errno;
-
- return btrfs_resize_loopback_fd(fd, new_size, grow_only);
-}
-
-int btrfs_qgroupid_make(uint64_t level, uint64_t id, uint64_t *ret) {
- assert(ret);
-
- if (level >= (UINT64_C(1) << (64 - BTRFS_QGROUP_LEVEL_SHIFT)))
- return -EINVAL;
-
- if (id >= (UINT64_C(1) << BTRFS_QGROUP_LEVEL_SHIFT))
- return -EINVAL;
-
- *ret = (level << BTRFS_QGROUP_LEVEL_SHIFT) | id;
- return 0;
-}
-
-int btrfs_qgroupid_split(uint64_t qgroupid, uint64_t *level, uint64_t *id) {
- assert(level || id);
-
- if (level)
- *level = qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT;
-
- if (id)
- *id = qgroupid & ((UINT64_C(1) << BTRFS_QGROUP_LEVEL_SHIFT) - 1);
-
- return 0;
-}
-
-static int qgroup_create_or_destroy(int fd, bool b, uint64_t qgroupid) {
-
- struct btrfs_ioctl_qgroup_create_args args = {
- .create = b,
- .qgroupid = qgroupid,
- };
- unsigned c;
- int r;
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (r == 0)
- return -ENOTTY;
-
- for (c = 0;; c++) {
- if (ioctl(fd, BTRFS_IOC_QGROUP_CREATE, &args) < 0) {
-
- /* If quota is not enabled, we get EINVAL. Turn this into a recognizable error */
- if (errno == EINVAL)
- return -ENOPROTOOPT;
-
- if (errno == EBUSY && c < 10) {
- (void) btrfs_quota_scan_wait(fd);
- continue;
- }
-
- return -errno;
- }
-
- break;
- }
-
- return 0;
-}
-
-int btrfs_qgroup_create(int fd, uint64_t qgroupid) {
- return qgroup_create_or_destroy(fd, true, qgroupid);
-}
-
-int btrfs_qgroup_destroy(int fd, uint64_t qgroupid) {
- return qgroup_create_or_destroy(fd, false, qgroupid);
-}
-
-int btrfs_qgroup_destroy_recursive(int fd, uint64_t qgroupid) {
- _cleanup_free_ uint64_t *qgroups = NULL;
- uint64_t subvol_id;
- int i, n, r;
-
- /* Destroys the specified qgroup, but unassigns it from all
- * its parents first. Also, it recursively destroys all
- * qgroups it is assgined to that have the same id part of the
- * qgroupid as the specified group. */
-
- r = btrfs_qgroupid_split(qgroupid, NULL, &subvol_id);
- if (r < 0)
- return r;
-
- n = btrfs_qgroup_find_parents(fd, qgroupid, &qgroups);
- if (n < 0)
- return n;
-
- for (i = 0; i < n; i++) {
- uint64_t id;
-
- r = btrfs_qgroupid_split(qgroups[i], NULL, &id);
- if (r < 0)
- return r;
-
- r = btrfs_qgroup_unassign(fd, qgroupid, qgroups[i]);
- if (r < 0)
- return r;
-
- if (id != subvol_id)
- continue;
-
- /* The parent qgroupid shares the same id part with
- * us? If so, destroy it too. */
-
- (void) btrfs_qgroup_destroy_recursive(fd, qgroups[i]);
- }
-
- return btrfs_qgroup_destroy(fd, qgroupid);
-}
-
-int btrfs_quota_scan_start(int fd) {
- struct btrfs_ioctl_quota_rescan_args args = {};
-
- assert(fd >= 0);
-
- if (ioctl(fd, BTRFS_IOC_QUOTA_RESCAN, &args) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_quota_scan_wait(int fd) {
- assert(fd >= 0);
-
- if (ioctl(fd, BTRFS_IOC_QUOTA_RESCAN_WAIT) < 0)
- return -errno;
-
- return 0;
-}
-
-int btrfs_quota_scan_ongoing(int fd) {
- struct btrfs_ioctl_quota_rescan_args args = {};
-
- assert(fd >= 0);
-
- if (ioctl(fd, BTRFS_IOC_QUOTA_RESCAN_STATUS, &args) < 0)
- return -errno;
-
- return !!args.flags;
-}
-
-static int qgroup_assign_or_unassign(int fd, bool b, uint64_t child, uint64_t parent) {
- struct btrfs_ioctl_qgroup_assign_args args = {
- .assign = b,
- .src = child,
- .dst = parent,
- };
- unsigned c;
- int r;
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (r == 0)
- return -ENOTTY;
-
- for (c = 0;; c++) {
- r = ioctl(fd, BTRFS_IOC_QGROUP_ASSIGN, &args);
- if (r < 0) {
- if (errno == EBUSY && c < 10) {
- (void) btrfs_quota_scan_wait(fd);
- continue;
- }
-
- return -errno;
- }
-
- if (r == 0)
- return 0;
-
- /* If the return value is > 0, we need to request a rescan */
-
- (void) btrfs_quota_scan_start(fd);
- return 1;
- }
-}
-
-int btrfs_qgroup_assign(int fd, uint64_t child, uint64_t parent) {
- return qgroup_assign_or_unassign(fd, true, child, parent);
-}
-
-int btrfs_qgroup_unassign(int fd, uint64_t child, uint64_t parent) {
- return qgroup_assign_or_unassign(fd, false, child, parent);
-}
-
-static int subvol_remove_children(int fd, const char *subvolume, uint64_t subvol_id, BtrfsRemoveFlags flags) {
- struct btrfs_ioctl_search_args args = {
- .key.tree_id = BTRFS_ROOT_TREE_OBJECTID,
-
- .key.min_objectid = BTRFS_FIRST_FREE_OBJECTID,
- .key.max_objectid = BTRFS_LAST_FREE_OBJECTID,
-
- .key.min_type = BTRFS_ROOT_BACKREF_KEY,
- .key.max_type = BTRFS_ROOT_BACKREF_KEY,
-
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- struct btrfs_ioctl_vol_args vol_args = {};
- _cleanup_close_ int subvol_fd = -1;
- struct stat st;
- bool made_writable = false;
- int r;
-
- assert(fd >= 0);
- assert(subvolume);
-
- if (fstat(fd, &st) < 0)
- return -errno;
-
- if (!S_ISDIR(st.st_mode))
- return -EINVAL;
-
- subvol_fd = openat(fd, subvolume, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (subvol_fd < 0)
- return -errno;
-
- if (subvol_id == 0) {
- r = btrfs_subvol_get_id_fd(subvol_fd, &subvol_id);
- if (r < 0)
- return r;
- }
-
- /* First, try to remove the subvolume. If it happens to be
- * already empty, this will just work. */
- strncpy(vol_args.name, subvolume, sizeof(vol_args.name)-1);
- if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &vol_args) >= 0) {
- (void) btrfs_qgroup_destroy_recursive(fd, subvol_id); /* for the leaf subvolumes, the qgroup id is identical to the subvol id */
- return 0;
- }
- if (!(flags & BTRFS_REMOVE_RECURSIVE) || errno != ENOTEMPTY)
- return -errno;
-
- /* OK, the subvolume is not empty, let's look for child
- * subvolumes, and remove them, first */
-
- args.key.min_offset = args.key.max_offset = subvol_id;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0)
- return -errno;
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
- _cleanup_free_ char *p = NULL;
- const struct btrfs_root_ref *ref;
- struct btrfs_ioctl_ino_lookup_args ino_args;
-
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->type != BTRFS_ROOT_BACKREF_KEY)
- continue;
- if (sh->offset != subvol_id)
- continue;
-
- ref = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
-
- p = strndup((char*) ref + sizeof(struct btrfs_root_ref), le64toh(ref->name_len));
- if (!p)
- return -ENOMEM;
-
- zero(ino_args);
- ino_args.treeid = subvol_id;
- ino_args.objectid = htole64(ref->dirid);
-
- if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &ino_args) < 0)
- return -errno;
-
- if (!made_writable) {
- r = btrfs_subvol_set_read_only_fd(subvol_fd, false);
- if (r < 0)
- return r;
-
- made_writable = true;
- }
-
- if (isempty(ino_args.name))
- /* Subvolume is in the top-level
- * directory of the subvolume. */
- r = subvol_remove_children(subvol_fd, p, sh->objectid, flags);
- else {
- _cleanup_close_ int child_fd = -1;
-
- /* Subvolume is somewhere further down,
- * hence we need to open the
- * containing directory first */
-
- child_fd = openat(subvol_fd, ino_args.name, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (child_fd < 0)
- return -errno;
-
- r = subvol_remove_children(child_fd, p, sh->objectid, flags);
- }
- if (r < 0)
- return r;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
- /* OK, the child subvolumes should all be gone now, let's try
- * again to remove the subvolume */
- if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &vol_args) < 0)
- return -errno;
-
- (void) btrfs_qgroup_destroy_recursive(fd, subvol_id);
- return 0;
-}
-
-int btrfs_subvol_remove(const char *path, BtrfsRemoveFlags flags) {
- _cleanup_close_ int fd = -1;
- const char *subvolume;
- int r;
-
- assert(path);
-
- r = extract_subvolume_name(path, &subvolume);
- if (r < 0)
- return r;
-
- fd = open_parent(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (fd < 0)
- return fd;
-
- return subvol_remove_children(fd, subvolume, 0, flags);
-}
-
-int btrfs_subvol_remove_fd(int fd, const char *subvolume, BtrfsRemoveFlags flags) {
- return subvol_remove_children(fd, subvolume, 0, flags);
-}
-
-int btrfs_qgroup_copy_limits(int fd, uint64_t old_qgroupid, uint64_t new_qgroupid) {
-
- struct btrfs_ioctl_search_args args = {
- /* Tree of quota items */
- .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID,
-
- /* The object ID is always 0 */
- .key.min_objectid = 0,
- .key.max_objectid = 0,
-
- /* Look precisely for the quota items */
- .key.min_type = BTRFS_QGROUP_LIMIT_KEY,
- .key.max_type = BTRFS_QGROUP_LIMIT_KEY,
-
- /* For our qgroup */
- .key.min_offset = old_qgroupid,
- .key.max_offset = old_qgroupid,
-
- /* No restrictions on the other components */
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- int r;
-
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) {
- if (errno == ENOENT) /* quota tree missing: quota is not enabled, hence nothing to copy */
- break;
-
- return -errno;
- }
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
- const struct btrfs_qgroup_limit_item *qli = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
- struct btrfs_ioctl_qgroup_limit_args qargs;
- unsigned c;
-
- /* Make sure we start the next search at least from this entry */
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->objectid != 0)
- continue;
- if (sh->type != BTRFS_QGROUP_LIMIT_KEY)
- continue;
- if (sh->offset != old_qgroupid)
- continue;
-
- /* We found the entry, now copy things over. */
-
- qargs = (struct btrfs_ioctl_qgroup_limit_args) {
- .qgroupid = new_qgroupid,
-
- .lim.max_rfer = le64toh(qli->max_rfer),
- .lim.max_excl = le64toh(qli->max_excl),
- .lim.rsv_rfer = le64toh(qli->rsv_rfer),
- .lim.rsv_excl = le64toh(qli->rsv_excl),
-
- .lim.flags = le64toh(qli->flags) & (BTRFS_QGROUP_LIMIT_MAX_RFER|
- BTRFS_QGROUP_LIMIT_MAX_EXCL|
- BTRFS_QGROUP_LIMIT_RSV_RFER|
- BTRFS_QGROUP_LIMIT_RSV_EXCL),
- };
-
- for (c = 0;; c++) {
- if (ioctl(fd, BTRFS_IOC_QGROUP_LIMIT, &qargs) < 0) {
- if (errno == EBUSY && c < 10) {
- (void) btrfs_quota_scan_wait(fd);
- continue;
- }
- return -errno;
- }
-
- break;
- }
-
- return 1;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
- return 0;
-}
-
-static int copy_quota_hierarchy(int fd, uint64_t old_subvol_id, uint64_t new_subvol_id) {
- _cleanup_free_ uint64_t *old_qgroups = NULL, *old_parent_qgroups = NULL;
- bool copy_from_parent = false, insert_intermediary_qgroup = false;
- int n_old_qgroups, n_old_parent_qgroups, r, i;
- uint64_t old_parent_id;
-
- assert(fd >= 0);
-
- /* Copies a reduced form of quota information from the old to
- * the new subvolume. */
-
- n_old_qgroups = btrfs_qgroup_find_parents(fd, old_subvol_id, &old_qgroups);
- if (n_old_qgroups <= 0) /* Nothing to copy */
- return n_old_qgroups;
-
- r = btrfs_subvol_get_parent(fd, old_subvol_id, &old_parent_id);
- if (r == -ENXIO)
- /* We have no parent, hence nothing to copy. */
- n_old_parent_qgroups = 0;
- else if (r < 0)
- return r;
- else {
- n_old_parent_qgroups = btrfs_qgroup_find_parents(fd, old_parent_id, &old_parent_qgroups);
- if (n_old_parent_qgroups < 0)
- return n_old_parent_qgroups;
- }
-
- for (i = 0; i < n_old_qgroups; i++) {
- uint64_t id;
- int j;
-
- r = btrfs_qgroupid_split(old_qgroups[i], NULL, &id);
- if (r < 0)
- return r;
-
- if (id == old_subvol_id) {
- /* The old subvolume was member of a qgroup
- * that had the same id, but a different level
- * as it self. Let's set up something similar
- * in the destination. */
- insert_intermediary_qgroup = true;
- break;
- }
-
- for (j = 0; j < n_old_parent_qgroups; j++)
- if (old_parent_qgroups[j] == old_qgroups[i]) {
- /* The old subvolume shared a common
- * parent qgroup with its parent
- * subvolume. Let's set up something
- * similar in the destination. */
- copy_from_parent = true;
- }
- }
-
- if (!insert_intermediary_qgroup && !copy_from_parent)
- return 0;
-
- return btrfs_subvol_auto_qgroup_fd(fd, new_subvol_id, insert_intermediary_qgroup);
-}
-
-static int copy_subtree_quota_limits(int fd, uint64_t old_subvol, uint64_t new_subvol) {
- uint64_t old_subtree_qgroup, new_subtree_qgroup;
- bool changed;
- int r;
-
- /* First copy the leaf limits */
- r = btrfs_qgroup_copy_limits(fd, old_subvol, new_subvol);
- if (r < 0)
- return r;
- changed = r > 0;
-
- /* Then, try to copy the subtree limits, if there are any. */
- r = btrfs_subvol_find_subtree_qgroup(fd, old_subvol, &old_subtree_qgroup);
- if (r < 0)
- return r;
- if (r == 0)
- return changed;
-
- r = btrfs_subvol_find_subtree_qgroup(fd, new_subvol, &new_subtree_qgroup);
- if (r < 0)
- return r;
- if (r == 0)
- return changed;
-
- r = btrfs_qgroup_copy_limits(fd, old_subtree_qgroup, new_subtree_qgroup);
- if (r != 0)
- return r;
-
- return changed;
-}
-
-static int subvol_snapshot_children(int old_fd, int new_fd, const char *subvolume, uint64_t old_subvol_id, BtrfsSnapshotFlags flags) {
-
- struct btrfs_ioctl_search_args args = {
- .key.tree_id = BTRFS_ROOT_TREE_OBJECTID,
-
- .key.min_objectid = BTRFS_FIRST_FREE_OBJECTID,
- .key.max_objectid = BTRFS_LAST_FREE_OBJECTID,
-
- .key.min_type = BTRFS_ROOT_BACKREF_KEY,
- .key.max_type = BTRFS_ROOT_BACKREF_KEY,
-
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- struct btrfs_ioctl_vol_args_v2 vol_args = {
- .flags = flags & BTRFS_SNAPSHOT_READ_ONLY ? BTRFS_SUBVOL_RDONLY : 0,
- .fd = old_fd,
- };
- _cleanup_close_ int subvolume_fd = -1;
- uint64_t new_subvol_id;
- int r;
-
- assert(old_fd >= 0);
- assert(new_fd >= 0);
- assert(subvolume);
-
- strncpy(vol_args.name, subvolume, sizeof(vol_args.name)-1);
-
- if (ioctl(new_fd, BTRFS_IOC_SNAP_CREATE_V2, &vol_args) < 0)
- return -errno;
-
- if (!(flags & BTRFS_SNAPSHOT_RECURSIVE) &&
- !(flags & BTRFS_SNAPSHOT_QUOTA))
- return 0;
-
- if (old_subvol_id == 0) {
- r = btrfs_subvol_get_id_fd(old_fd, &old_subvol_id);
- if (r < 0)
- return r;
- }
-
- r = btrfs_subvol_get_id(new_fd, vol_args.name, &new_subvol_id);
- if (r < 0)
- return r;
-
- if (flags & BTRFS_SNAPSHOT_QUOTA)
- (void) copy_quota_hierarchy(new_fd, old_subvol_id, new_subvol_id);
-
- if (!(flags & BTRFS_SNAPSHOT_RECURSIVE)) {
-
- if (flags & BTRFS_SNAPSHOT_QUOTA)
- (void) copy_subtree_quota_limits(new_fd, old_subvol_id, new_subvol_id);
-
- return 0;
- }
-
- args.key.min_offset = args.key.max_offset = old_subvol_id;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(old_fd, BTRFS_IOC_TREE_SEARCH, &args) < 0)
- return -errno;
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
- _cleanup_free_ char *p = NULL, *c = NULL, *np = NULL;
- struct btrfs_ioctl_ino_lookup_args ino_args;
- const struct btrfs_root_ref *ref;
- _cleanup_close_ int old_child_fd = -1, new_child_fd = -1;
-
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->type != BTRFS_ROOT_BACKREF_KEY)
- continue;
-
- /* Avoid finding the source subvolume a second
- * time */
- if (sh->offset != old_subvol_id)
- continue;
-
- /* Avoid running into loops if the new
- * subvolume is below the old one. */
- if (sh->objectid == new_subvol_id)
- continue;
-
- ref = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh);
- p = strndup((char*) ref + sizeof(struct btrfs_root_ref), le64toh(ref->name_len));
- if (!p)
- return -ENOMEM;
-
- zero(ino_args);
- ino_args.treeid = old_subvol_id;
- ino_args.objectid = htole64(ref->dirid);
-
- if (ioctl(old_fd, BTRFS_IOC_INO_LOOKUP, &ino_args) < 0)
- return -errno;
-
- /* The kernel returns an empty name if the
- * subvolume is in the top-level directory,
- * and otherwise appends a slash, so that we
- * can just concatenate easily here, without
- * adding a slash. */
- c = strappend(ino_args.name, p);
- if (!c)
- return -ENOMEM;
-
- old_child_fd = openat(old_fd, c, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (old_child_fd < 0)
- return -errno;
-
- np = strjoin(subvolume, "/", ino_args.name, NULL);
- if (!np)
- return -ENOMEM;
-
- new_child_fd = openat(new_fd, np, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (new_child_fd < 0)
- return -errno;
-
- if (flags & BTRFS_SNAPSHOT_READ_ONLY) {
- /* If the snapshot is read-only we
- * need to mark it writable
- * temporarily, to put the subsnapshot
- * into place. */
-
- if (subvolume_fd < 0) {
- subvolume_fd = openat(new_fd, subvolume, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (subvolume_fd < 0)
- return -errno;
- }
-
- r = btrfs_subvol_set_read_only_fd(subvolume_fd, false);
- if (r < 0)
- return r;
- }
-
- /* When btrfs clones the subvolumes, child
- * subvolumes appear as empty directories. Remove
- * them, so that we can create a new snapshot
- * in their place */
- if (unlinkat(new_child_fd, p, AT_REMOVEDIR) < 0) {
- int k = -errno;
-
- if (flags & BTRFS_SNAPSHOT_READ_ONLY)
- (void) btrfs_subvol_set_read_only_fd(subvolume_fd, true);
-
- return k;
- }
-
- r = subvol_snapshot_children(old_child_fd, new_child_fd, p, sh->objectid, flags & ~BTRFS_SNAPSHOT_FALLBACK_COPY);
-
- /* Restore the readonly flag */
- if (flags & BTRFS_SNAPSHOT_READ_ONLY) {
- int k;
-
- k = btrfs_subvol_set_read_only_fd(subvolume_fd, true);
- if (r >= 0 && k < 0)
- return k;
- }
-
- if (r < 0)
- return r;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
- if (flags & BTRFS_SNAPSHOT_QUOTA)
- (void) copy_subtree_quota_limits(new_fd, old_subvol_id, new_subvol_id);
-
- return 0;
-}
-
-int btrfs_subvol_snapshot_fd(int old_fd, const char *new_path, BtrfsSnapshotFlags flags) {
- _cleanup_close_ int new_fd = -1;
- const char *subvolume;
- int r;
-
- assert(old_fd >= 0);
- assert(new_path);
-
- r = btrfs_is_subvol_fd(old_fd);
- if (r < 0)
- return r;
- if (r == 0) {
- if (!(flags & BTRFS_SNAPSHOT_FALLBACK_COPY))
- return -EISDIR;
-
- r = btrfs_subvol_make(new_path);
- if (r < 0)
- return r;
-
- r = copy_directory_fd(old_fd, new_path, true);
- if (r < 0) {
- (void) btrfs_subvol_remove(new_path, BTRFS_REMOVE_QUOTA);
- return r;
- }
-
- if (flags & BTRFS_SNAPSHOT_READ_ONLY) {
- r = btrfs_subvol_set_read_only(new_path, true);
- if (r < 0) {
- (void) btrfs_subvol_remove(new_path, BTRFS_REMOVE_QUOTA);
- return r;
- }
- }
-
- return 0;
- }
-
- r = extract_subvolume_name(new_path, &subvolume);
- if (r < 0)
- return r;
-
- new_fd = open_parent(new_path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (new_fd < 0)
- return new_fd;
-
- return subvol_snapshot_children(old_fd, new_fd, subvolume, 0, flags);
-}
-
-int btrfs_subvol_snapshot(const char *old_path, const char *new_path, BtrfsSnapshotFlags flags) {
- _cleanup_close_ int old_fd = -1;
-
- assert(old_path);
- assert(new_path);
-
- old_fd = open(old_path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (old_fd < 0)
- return -errno;
-
- return btrfs_subvol_snapshot_fd(old_fd, new_path, flags);
-}
-
-int btrfs_qgroup_find_parents(int fd, uint64_t qgroupid, uint64_t **ret) {
-
- struct btrfs_ioctl_search_args args = {
- /* Tree of quota items */
- .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID,
-
- /* Look precisely for the quota relation items */
- .key.min_type = BTRFS_QGROUP_RELATION_KEY,
- .key.max_type = BTRFS_QGROUP_RELATION_KEY,
-
- /* No restrictions on the other components */
- .key.min_offset = 0,
- .key.max_offset = (uint64_t) -1,
-
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
-
- _cleanup_free_ uint64_t *items = NULL;
- size_t n_items = 0, n_allocated = 0;
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- if (qgroupid == 0) {
- r = btrfs_subvol_get_id_fd(fd, &qgroupid);
- if (r < 0)
- return r;
- } else {
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
- }
-
- args.key.min_objectid = args.key.max_objectid = qgroupid;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) {
- if (errno == ENOENT) /* quota tree missing: quota is disabled */
- break;
-
- return -errno;
- }
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
-
- /* Make sure we start the next search at least from this entry */
- btrfs_ioctl_search_args_set(&args, sh);
-
- if (sh->type != BTRFS_QGROUP_RELATION_KEY)
- continue;
- if (sh->offset < sh->objectid)
- continue;
- if (sh->objectid != qgroupid)
- continue;
-
- if (!GREEDY_REALLOC(items, n_allocated, n_items+1))
- return -ENOMEM;
-
- items[n_items++] = sh->offset;
- }
-
- /* Increase search key by one, to read the next item, if we can. */
- if (!btrfs_ioctl_search_args_inc(&args))
- break;
- }
-
- if (n_items <= 0) {
- *ret = NULL;
- return 0;
- }
-
- *ret = items;
- items = NULL;
-
- return (int) n_items;
-}
-
-int btrfs_subvol_auto_qgroup_fd(int fd, uint64_t subvol_id, bool insert_intermediary_qgroup) {
- _cleanup_free_ uint64_t *qgroups = NULL;
- uint64_t parent_subvol;
- bool changed = false;
- int n = 0, r;
-
- assert(fd >= 0);
-
- /*
- * Sets up the specified subvolume's qgroup automatically in
- * one of two ways:
- *
- * If insert_intermediary_qgroup is false, the subvolume's
- * leaf qgroup will be assigned to the same parent qgroups as
- * the subvolume's parent subvolume.
- *
- * If insert_intermediary_qgroup is true a new intermediary
- * higher-level qgroup is created, with a higher level number,
- * but reusing the id of the subvolume. The level number is
- * picked as one smaller than the lowest level qgroup the
- * parent subvolume is a member of. If the parent subvolume's
- * leaf qgroup is assigned to no higher-level qgroup a new
- * qgroup of level 255 is created instead. Either way, the new
- * qgroup is then assigned to the parent's higher-level
- * qgroup, and the subvolume itself is assigned to it.
- *
- * If the subvolume is already assigned to a higher level
- * qgroup, no operation is executed.
- *
- * Effectively this means: regardless if
- * insert_intermediary_qgroup is true or not, after this
- * function is invoked the subvolume will be accounted within
- * the same qgroups as the parent. However, if it is true, it
- * will also get its own higher-level qgroup, which may in
- * turn be used by subvolumes created beneath this subvolume
- * later on.
- *
- * This hence defines a simple default qgroup setup for
- * subvolumes, as long as this function is invoked on each
- * created subvolume: each subvolume is always accounting
- * together with its immediate parents. Optionally, if
- * insert_intermediary_qgroup is true, it will also get a
- * qgroup that then includes all its own child subvolumes.
- */
-
- if (subvol_id == 0) {
- r = btrfs_is_subvol_fd(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
-
- r = btrfs_subvol_get_id_fd(fd, &subvol_id);
- if (r < 0)
- return r;
- }
-
- n = btrfs_qgroup_find_parents(fd, subvol_id, &qgroups);
- if (n < 0)
- return n;
- if (n > 0) /* already parent qgroups set up, let's bail */
- return 0;
-
- qgroups = mfree(qgroups);
-
- r = btrfs_subvol_get_parent(fd, subvol_id, &parent_subvol);
- if (r == -ENXIO)
- /* No parent, hence no qgroup memberships */
- n = 0;
- else if (r < 0)
- return r;
- else {
- n = btrfs_qgroup_find_parents(fd, parent_subvol, &qgroups);
- if (n < 0)
- return n;
- }
-
- if (insert_intermediary_qgroup) {
- uint64_t lowest = 256, new_qgroupid;
- bool created = false;
- int i;
-
- /* Determine the lowest qgroup that the parent
- * subvolume is assigned to. */
-
- for (i = 0; i < n; i++) {
- uint64_t level;
-
- r = btrfs_qgroupid_split(qgroups[i], &level, NULL);
- if (r < 0)
- return r;
-
- if (level < lowest)
- lowest = level;
- }
-
- if (lowest <= 1) /* There are no levels left we could use insert an intermediary qgroup at */
- return -EBUSY;
-
- r = btrfs_qgroupid_make(lowest - 1, subvol_id, &new_qgroupid);
- if (r < 0)
- return r;
-
- /* Create the new intermediary group, unless it already exists */
- r = btrfs_qgroup_create(fd, new_qgroupid);
- if (r < 0 && r != -EEXIST)
- return r;
- if (r >= 0)
- changed = created = true;
-
- for (i = 0; i < n; i++) {
- r = btrfs_qgroup_assign(fd, new_qgroupid, qgroups[i]);
- if (r < 0 && r != -EEXIST) {
- if (created)
- (void) btrfs_qgroup_destroy_recursive(fd, new_qgroupid);
-
- return r;
- }
- if (r >= 0)
- changed = true;
- }
-
- r = btrfs_qgroup_assign(fd, subvol_id, new_qgroupid);
- if (r < 0 && r != -EEXIST) {
- if (created)
- (void) btrfs_qgroup_destroy_recursive(fd, new_qgroupid);
- return r;
- }
- if (r >= 0)
- changed = true;
-
- } else {
- int i;
-
- /* Assign our subvolume to all the same qgroups as the parent */
-
- for (i = 0; i < n; i++) {
- r = btrfs_qgroup_assign(fd, subvol_id, qgroups[i]);
- if (r < 0 && r != -EEXIST)
- return r;
- if (r >= 0)
- changed = true;
- }
- }
-
- return changed;
-}
-
-int btrfs_subvol_auto_qgroup(const char *path, uint64_t subvol_id, bool create_intermediary_qgroup) {
- _cleanup_close_ int fd = -1;
-
- fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
- if (fd < 0)
- return -errno;
-
- return btrfs_subvol_auto_qgroup_fd(fd, subvol_id, create_intermediary_qgroup);
-}
-
-int btrfs_subvol_get_parent(int fd, uint64_t subvol_id, uint64_t *ret) {
-
- struct btrfs_ioctl_search_args args = {
- /* Tree of tree roots */
- .key.tree_id = BTRFS_ROOT_TREE_OBJECTID,
-
- /* Look precisely for the subvolume items */
- .key.min_type = BTRFS_ROOT_BACKREF_KEY,
- .key.max_type = BTRFS_ROOT_BACKREF_KEY,
-
- /* No restrictions on the other components */
- .key.min_offset = 0,
- .key.max_offset = (uint64_t) -1,
-
- .key.min_transid = 0,
- .key.max_transid = (uint64_t) -1,
- };
- int r;
-
- assert(fd >= 0);
- assert(ret);
-
- if (subvol_id == 0) {
- r = btrfs_subvol_get_id_fd(fd, &subvol_id);
- if (r < 0)
- return r;
- } else {
- r = btrfs_is_filesystem(fd);
- if (r < 0)
- return r;
- if (!r)
- return -ENOTTY;
- }
-
- args.key.min_objectid = args.key.max_objectid = subvol_id;
-
- while (btrfs_ioctl_search_args_compare(&args) <= 0) {
- const struct btrfs_ioctl_search_header *sh;
- unsigned i;
-
- args.key.nr_items = 256;
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0)
- return negative_errno();
-
- if (args.key.nr_items <= 0)
- break;
-
- FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) {
-
- if (sh->type != BTRFS_ROOT_BACKREF_KEY)
- continue;
- if (sh->objectid != subvol_id)
- continue;
-
- *ret = sh->offset;
- return 0;
- }
- }
-
- return -ENXIO;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 10:42:39 +0000